Smartphone shoulder strap



FIG. 1 illustrates a perspective view of a smartphone shoulder strap showing my new design;

FIG. 2 illustrates a side view thereof;

FIG. 3 illustrates a front view thereof;

FIG. 4 illustrates a rear view thereof;

FIG. 5 illustrates a top view thereof; and,

FIG. 6 illustrates a bottom view thereof. 

CLAIM The ornamental design for a smartphone shoulder strap, as shown and described. 